In computer architecture, a bus (bidirectional universal switch) is a subsystem that transfers data or power between computer components inside a computer or between computers, and a bus typically is controlled by device driver software.
Parallel interface means that different devices (physical or logical) communicate in a serial way. Example A wants to speak with E Then A would communicate like this: A ->BA ->CA ->DA ->E
method for connecting an external device such as a printer, scanner, or camera, to a computer. It has been all but replaced by USB and FireWire in modern computers.
SCSI (Small Computer System Interface) is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and opticalinterfaces.
In telecommunications, RS-232 (Recommended Standard 232) is a standard for serial binary data signals connecting between a DTE (Data terminal equipment) and a DCE (Data Circuit-terminating Equipment). It is commonly used in computer serial ports.
A very fast external bus that supports data transfer rates of up to 400 Mbps. Firewire was developed by Apple and falls under the IEEE 1394 standard. Other companies follow the IEEE 1394 but have names such as Lynx and I-Link.
A hard disk drive (HDD), commonly referred to as a hard drive or hard disk,[1] is a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces.
Single In-line Memory Module. A small circuit board with integrated circuit chips used to hold RAM (Random Access Memory). SIMMS clip into the memory bank sockets on the motherboard.
Random access memory (usually known by its acronym, RAM) is a type of data storage used in computers. It takes the form of integrated circuits that allow the stored data to be accessed in any order � that is, at random and without the physical movement of the storage medium or a physical reading head.
A network card, network adapter or NIC (network interface card) is a piece of computer hardware designed to allow computers to communicate over a computer
A modem (a portmanteau word constructed from modulator and demodulator) is a device that modulates an analog carrier signal (sound), to encode digital information, and that also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data.
The binary or base-two numeral system is a system for representing numbers in which a radix of two is used; that is, each digit in a binary numeral may have either of two different values. Typically, the symbols 0 and 1 are used to represent binary numbers. Owing to its relatively straightforward implementation in electronic circuitry, the binary system is used internally by virtually all modern computers.
A numbering system which uses a base of 16. The first ten digits are 0-9 and the next six are AF. Hexadecimal numbers are used to color web pages. For example, the hexadecimal equivalent for the color white is #FFFFFF.
One of the four number groups in an IP address. Although it is three decimal digits, it is derived from an eight-digit binary number, hence the term 'octet'.
ASCII: A digital code for print characters, including those on a standard keyboard. It stands for the American Standard Code for Information Inter-change,
Standard Generalized Markup Language. SGML is both a language and an ISO standard for describing information embedded within a document. HyperText Markup Language (HTML) is based on the SGML standard.
In computing, HyperText Markup Language (HTML) is a markup language designed for the creation of web pages and other information viewable in a browser. HTML is used to structure information -- denoting certain text as headings, paragraphs, lists and so on -- and can be used to define the semantics of a document.
Short for Extensible Markup Language, a specification developed by the W3C. XML is a pared-down version of SGML, designed especially for Web documents. It allows designers to create their own customized tags, enabling the definition, transmission, validation, and interpretation of data between applications and between organizations.
A collection of alphabets in a similar style but in different weights or classifications. For example, the Garamond font family might include Garamond, Garamond Bold, Garamond Italic, and Garamond Bold Italic.
In typography, a point is the smallest unit of measure, it being the subdivision of the pica. It is commonly abbreviated as pt. The traditional printer's point from the era of hot metal typesetting and presswork varied between 0.18 and 0.4 mm depending on various definitions of the foot. Today, the traditional point has been supplanted by the desktop publishing point (also called the PostScript point), which has been rounded to an even 72 points to the inch (1 point = 0.3527 mm). In either system, there are 12 points to the pica.
In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language.
HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. The original purpose was to provide a way to publish and receive HTML pages.
A Uniform Resource Identifier (URI), is a compact string of characters used to identify or name a resource. The main purpose of this identification is to enable interaction with representations of the resource over a network, typically the World Wide Web, using specific protocols. URIs are defined in schemes defining a specific syntax and associated protocols.
Blog is short for weblog. A weblog is a journal (or newsletter) that is frequently updated and intended for general public consumption. Blogs generally represent the personality of the author or the Web site.
Network neutrality (equivalently "net neutrality", "Internet neutrality" or "NN") refers to a principle that is applied to residential broadband networks, and potentially to all networks. Precise definitions vary, but a broadband network free of restrictions on the kinds of equipment that may be attached and the modes of communication allowed, and where communication was not unreasonably degraded by other communication streams would be considered neutral by most advocates.
Its most familiar modern use is in e-mail addresses (sent by SMTP), as in jdoe@example.com ("the user named �jdoe� working at the computer named �example� in the �com� domain").
In Unix shells, the tilde indicates the current user's home directory (e.g., /home/username). When prepended to a particular username, it indicates that user's home directory (e.g., ~janedoe for the home directory of user janedoe, typically /home/janedoe). When some Unix shell commands overwrite a file, they can be made to keep a backup by renaming the original file as filename~.
On Unix-like systems, the slash carries two distinct meanings. Its primary use, as with URLs, is to separate directory and file components of a path: pictures/image.jpg
A leading slash however represents the root directory of the virtual file system; it is used when specifying absolute paths: /home/joe/pictures/image.jpg
Peer-to-Peer: A system in which two or more nodes or processes can initiate communications with each other. Usually describes a network in which all nodes have the ability to share resources with other nodes so that a dedicated server can be implemented but is not required.
The term applied to networks having bandwidths significantly greater than that found in telephony networks. Broadband systems are capable of carrying a large number of moving images or a vast quantity of data simultaneously. Broadband techniques usually depend on coaxial or optical cable for transmissions. They utilize multiplexing to permit the simultaneous operation of multiple channels or services on a single cable. Frequency division multiplexing or cell relay techniques can both be used in broadband transmission.
BitTorrent is a peer-to-peer (P2P) communications protocol for file sharing. The protocol was designed in April 2001 and implemented in Summer 2002 by programmer Bram Cohen, and is now maintained by BitTorrent, Inc.
File Server - A computer connected to the network that contains primary files/applications and shares them as requested with the other computers on the network. If the file server is dedicated for that purpose only, it is connected to a client/server network. An example of a client/server network is Novell Netware. All the computers connected to a peer-to-peer network are capable of being the file server. Two examples of peer-to-peer networks are LANtastic and Windows for Workgroups.
a local computer network for communication between computers; especially a network connecting computers and word processors and other electronic office equipment to create a communication system between offices)
National LambdaRail is a high-speed national computer network in the United States that runs over fiber-optic lines, and is the first transcontinental Ethernet network. The name is shared by the organization of research institutions that developed the network, and, to date, plans to continue developing it. LambdaRail is similar to the Abilene Network, but LambdaRail permits deeper experimentation than Abilene does.
A collection of Internet communication protocols between two computers. The TCP protocol is responsible for an error free connection between two computers, while the IP protocol is responsible for the data packets sent over the network.
A networking system in which one or more file servers (Server) provide services; such as network management, application and centralized data storage for workstations (Clients).
A device that can establish communication channels between end-users. A circuit switch provides dedicated paths to communicating entities; a store and forward switch shares paths on a statistically multiplexed basis.
In June 2003, a third modulation standard was ratified: 802.11g. This works in the 2.4 GHz band (like 802.11b) but operates at a maximum raw data rate of 54 Mbit/s, or about 19 Mbit/s net throughput. 802.11g hardware is fully backwards compatible with 802.11b hardware. The then-proposed 802.11g standard was rapidly adopted by consumers starting in January 2003, well before ratification, due to the desire for higher speeds, and reductions in manufacturing costs.
The Domain Name Server resolves the name of the Web site typed into the location field of the browser with the IP address of the server that will send the requested information from that Web site.
A deprecated element or attribute is one that has been outdated by newer constructs. Deprecated elements are defined in the reference manual in appropriate locations, but are clearly marked as deprecated. Deprecated elements may become obsolete in future versions of HTML.
(Document Type Definition) A DTD is the formal definition of the elements, structures, and rules for marking up a given type of SGML document. You can store a DTD at the beginning of a document or externally in a separate file.
Validation is a way to make sure that your code is compliant with the W3C HTML specifications. Validation sites include Bobby and the W3C's Validation Service.
An XML document that follows the rules set forth by the XML specification, including having an XML declaration, correct comments, all tags are closed, all attributes are quoted, every document has one "container" element.
SGML (Standard Generalized Markup Language) is a standard for how to specify a document markup language or tag set. Such a specification is itself a document type definition (DTD). SGML is not in itself a document language, but a description of how to specify one. It is metadata.
Abbreviation for Extensible Hypertext Mark-up Language and is a hybrid of XML and HTML. Web pages designed in XHTML should look the same across all platforms.
a markup language for documents containing structured information. A markup language is a mechanism to identify structures in a document. The XML specification defines a standard way to add markup to documents.
Use this when you need to take advantage of HTML's presentational features and when you want to support browsers that don't understand Cascading Style Sheets.
The main workspace in a graphical user interface such as Windows or Macintosh Systems. Users open and work with files and programs on the desktop, and can store files and shortcuts there as well. The user can also customize the look of the desktop with images or wallpaper and custom icons.
In DOS and Microsoft Windows, the backslash as well as the forward slash are used as the delimiter between directories and filenames in path expressions. This is in contrast to Unix and Internet URLs (web addresses), which only use the forward slash.
In the twentieth century, following the development of formal logic, the ampersand became a commonly used logical notation for the binary operator or sentential connective AND. This usage was adopted in computing.
File Allocation Table resides on a data storage device (a hard disk or flash memory card) indicating the status and location of all data clusters that are on the device. The file allocation table can be considered a "table of contents" of a memory card. If the file allocation table is damaged or lost, then the card is unreadable. FAT16 and FAT32 standards differ in the width of the cluster address and the number of possible cluster addresses.
An advanced file system designed for use specifically within the Windows NT operating system. It supports file system recovery, extremely large storage media, long filenames, and various features for the POSIX subsystem. It also supports object-oriented applications by treating all files as objects with user-defined and system-defined attributes.
Infra Red. This uses a beam of light that is invisible to us humans to either control a device without wires or as a method of transferring data from camera to computer (or printer) without cables.
Operating System. The foundation software of a machine; that which schedules tasks, allocates storage, and presents a default interface to the user between applications. The facilities an operating system provides and its general design philosophy exert an extremely strong influence on programming style and on the technical cultures that grow up around its host machines.
IDE stands for Integrated/Intelligent Drive Electronics. It is an ATA specification (the terms are often used interchangably). This is the most common disk interface for hard drives, CD-ROM drives, etc. It is easy to use, but also the most limited. IDE is integrated into your motherboard. It only allows for 4 devices. The other option is SCSI which is faster, more complicated, and allows for many more devices. SCSI requires a separate add-on card and different types of hard drives (SCSI).
The state of having a file scattered around a disk in pieces rather than existing in one contiguous area of the disk. Fragmented files are slower to read than unfragmented files.
In general terms, a virtual machine in computer science is software that creates an environment between the computer platform and the end user in which the end user can operate software.
Computer hardware
Coding
Languages
Writing Styles
Internet access,navigation, and resources
A leading slash however represents the root directory of the virtual file system; it is used when specifying absolute paths: /home/joe/pictures/image.jpg
site
PC terms